Using the Mega 2560 and pin A0 to measure 0 - 4.5 volts. Analog reference set to DEFAULT. The problem is that the measurement with analogRead() works as it should only as long as the Arduino is connected to the PC via the USB cable. As soon as I disconnect the USB cable, the measurement returns ei…

Analog Reading Wrong When Disconnected From PC

Topic		Replies	Views
voltage/Analog input General Electronics	19	4196	May 6, 2021
Odd analogRead results with USB power General Guidance	8	5728	May 5, 2021
AREF not working? Sensors	9	3266	May 6, 2021
Incorrect output by AnalogRead Sensors	3	858	May 6, 2021
Changing/Fluctuating Analog Input IDE 1.x	7	2810	May 5, 2021